<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <meta name="viewport"content="width=device-width,initial-scale=1">
    <title>基础</title>
    <link href="../../../css/bootstrap.min.css" rel="stylesheet">
    <script src="../../../js/jquery-2.1.1.js"></script>
    <script src="../../../js/bootstrap.min.js"></script>
</head>
<body  style="margin: 50px 0px 0px 50px">
<div class="btn-group">
    <button type="button" class="btn btn-primary dropdown-toggle"    data-toggle="dropdown">
        原始 <span class="caret"></span>    </button>
    <ul class="dropdown-menu" role="menu">
        <li><a href="#">功能</a></li>
        <li><a href="#">另一个功能</a></li>
        <li><a href="#">其他</a></li>
        <li class="divider"></li>
        <li><a href="#">分离的链接</a></li>
    </ul>
</div>
<br/><br/><br/><br/><br/><br/><br/><br/><br/><br/>
分割的按钮下拉菜单
<br/><br/><br/>
<div class="btn-group dropup">
    <button type="button" class="btn btn-primary btn-large">原始</button>
    <button type="button" class="btn btn-primary dropdown-toggle"  data-toggle="dropdown">
        <span class="caret"></span>
        <span class="sr-only">切换下拉菜单</span>    </button>
    <ul class="dropdown-menu" role="menu">
        <li><a href="#">功能</a></li>
        <li><a href="#">另一个功能</a></li>
        <li><a href="#">其他</a></li>
        <li class="divider">divider</li>
        <li><a href="#">分离的链接</a></li>
    </ul>
</div>

</body>
</html>